| 摘要 |
PROBLEM TO BE SOLVED: To provide a constant current circuit which can output current not depending on the change of power source voltage. SOLUTION: A constant current circuit 41 includes a first NMOS transistor TN1 and a second NMOS transistor TN2 whose gates are connected. The second NMOS transistor TN2 has n times the element size of the first NMOS transistor TN1. The source of the first NMOS transistor TN1 is connected to a second power source line L2 for supplying low potential power source VSS. The source of the second NMOS transistor TN2 is connected to the second power source line L2 through a first resistor R11. The gates of the first and the second NMOS transistors TN1 and TN2 are connected to the gate of a sixth NMOS transistor TN6. The gate voltages of the first and the second NMOS transistor TN1 and TN2 are controlled so that drain currents coincide. COPYRIGHT: (C)2006,JPO&NCIPI
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